Arabidopsis 2010: Identifying Clients of 14-3-3 Phosphoregulation

University Of Florida, Gainesville FL

Investigators

Abstract

This project seeks to characterize the entire range of Arabidopsis proteins that are regulated by interaction with 14-3-3 proteins; to identify components from metabolic and signal transduction pathways that utilize 14-3-3 regulators, and to address fundamental aspects of 14-3-3 function in plants. 14-3-3s have emerged as critical regulators of important and diverse cellular processes that extend to every tissue and organ. Indeed, 14-3-3s appear to be intrinsically necessary for regulatory events that are absolutely crucial to normal growth and development in many species, and especially in plants. Initial searches of the Arabidopsis genome predict that 14-3-3s interact with fully 10 to 20 percent of the Arabidopsis gene products. The most recognized of 14-3-3 activities involve protein kinases, phosphorylation events and signal transduction pathways involved in growth and development, with one underlying theme being that 14-3-3s bind to specific phosphorylated client proteins in order to influence the regulation of the target activity. The goals of the present project are to identify in the Arabidopsis genome client proteins that possess 14-3-3 docking sites and to assay the interaction strength of the potential docking site against the family of 14-3-3 proteins in order to provide a tested, predictive algorithm for determining of the spectrum of 14-3-3 interactions that should be expected for each client protein. These data, combined with emerging data from 14-3-3 knockouts and 14-3-3 isoform expression patterns, should provide key insights into the potential regulatory functions of the 14-3-3 signal mediating molecules, and a central, fully characterized database for predicting 14-3-3 mediated signaling in diverse pathways. By highlighting potential regulatory sites across diverse gene families and metabolic pathways, this project will provide an integrating effect on the many projects identifying specific functional aspects of Arabidopsis gene families. As genes are functionally characterized, the 14-3-3 client database will provide immediate predictions of phosphorylation and 14-3-3 dependent regulation that will accelerate the understanding of the regulation of many gene families and metabolic and signaling pathways.